Expansion valve



Feb. 12, 1929. 1,702,186

s. E. WILSON EXPAN S I ON VALVE Filed Feb. 17, 1927 2 Sheet s-Sheet l awuemtoz 'Witmeooeo N R WL ZSOIZ 6 5671 Ema.

Feb. 12, 1929. 1,702,186

S. E. WILSON EXPANS I ON VALVE Filed Feb. 17, 1927 2 Sheets-Sheet 2 1 IIIIIIIII/ll I 3] v um 1 km m) M cameo 5 W? 071/ Patented Feb. 12, 1929.

UNITED STATES.

SIDNEY EUGENE WILSON, F LAUREL, MISSISSIPPI.

EXPANSION VALVE.

Application filed. February 1'7, 1927. Serial No. 169,068.

This invention relates to an expansion valve, especially adapted to be used in a refrigerating system, such, for example, as that shown in my co-pending application, Scrial No. 122,632, filed July 15, 1926.

Some of the more important objects of the invention are to provide an expansion valve of this type, which is simple and inexpensive in construction and reliable in operation, and which will maintain in a given degree of vacuum on the low pressure side at all times; to provide a device which permits visibility of operation; to provide a valve which may be used in either a wet or a dry system ot retrig oration, and which will automatically control the pressures at a predetermined point.

, The invention also embodies various novel features of construction which improve operation, and result in greater eliiciency. All these features will be more fully plained in the following detailed description taken in connection with the accompanying drawings, showing the preferred embodiment of the same.

In the drawings:

Figure 1 is a vertical section through a valve constructed according to my invention, and adapted particularly for use in a flooded system. V Figure 2 is a horizontal section taken on the line 2-2 of Figure 1.

Figure 3 is a detail view of the valve element and means for supporting the same.

Figure lis a view similar to Figure l, but showing the invention adapted to either a dry or a flooded system.

Figure 5 is a similar view showing the valve adapted particularly toa dry system.

The casing containing the valve may be very simply constructed, either in one casting, V or a plurality of castings rigidly secured together. In the form shown in Figures 1 and 2, the'casing comprisesanupper wall 10, and a lower wall 11 connected to each other by tie rods or bolts 12. The upper wall is formed on its inner face with concentric channels 13, and opposite these channels the lower wall is formed with similar channels 14. Cylindrical walls 15 and 16are seated in the channels encloses a chamber 17, and between the walls 15 and 16 is an outer annular chamber 18.

'The bottom wall 11 has a downward exten. 13 de hing a lower chamber Ell) the head 31, and support a check rod 38.

through which vapor passes on its way into the outer chamber 18, whence it passes to the compressor or condenser. Ports 21 connect the chamber with the chamber 18. An inlet'port 22 is formed in the wall 10 leading into the inner chamber17, and is connected by a pipe 23 with the high pressure side of the system. The wall 10 is also provided with an outlet port 24 leading from the chamber 18, and a pipe 25 leads from the port 2a back to the intake of the compressor.

The lower portion 19 of the lower wall is formed with a reduced threaded extension 26, adapted to be attached to a refrigerating unit, and extending downwardly within the extension 26 is a tube 2'7 secured to the inner portion of the wall 11, and providing an outlet from the inner chamber 17.

The passage of the refrigerant from the chamber 17 into the tube 27 is controlled by a conical valve 28. Located within'the chamber 17 is an expansible and contractible bellows 29 adapted to be controlled by temperature or pressure. This bellows is provided with a lower head 30 to which the valve 28 is secured, and an upper head 31 by which the bellows is supported. I

The bellows 29 is supported by a stem 32. which is secured in a suitable manner to the head 31. In the present instance, the stem has a threaded connection with a collar 33 through which the bellows may be charged before it is mounted. The stem 32 is supported in a plug 34 secured to the wall 10, the stem having a threaded connection 35 with the plug, so that the bellows and the valve carried thereby may be adjusted up or down. The connection of the stem 32 with the plug is closed by a suitable packing gland 36.

Studs 37 are secured to the inner faceroi valve 28 has a stem 39 formed at its upper end with a hook 40 engaging the check rod 38. so

as to positively prevent excessive expansion of the bellows.

In applying the valve to a refrigerating systennthe interior of the bellows 29 is charged with retrigerant,'and the conical valve 28 is adjusted to a closed position before the compression is started. In other words, the normal position of the valve is closed, all presures in the system being equal.

When compression is started, the inner chamber 17 which is connected with the high pressure side by the pipe 23, receives refrigerant unr pressure. in

the chamber 17 increases, the bellows is compressed, and the valve member 28 is raised. This allows the liquefied refrigerant to pass downwardly through the pipe 27 to the boiler. This initial compression of the bellows is due to the increase of pressure outside the bellows. Subsequent compressions of the bellows may be from the'joint action of pressure and temperature.

The next step in'the action of the valve is absorption of heatby the volatile substance within the bellows, and the consequent expansion. of the same which results in again expanding the bellows and Closing he valve continues, the cold gas returning from the ,perature and partly by pressure in such a way that the refrigerating liquid and lubricant will pass fromthe high side without passing any gas. It will pass the gas and any excess of lubricant from the boiler back through the outer chamber 18 to the compressor. The action is entirely automatic, and will continue without adjustment or attention. V

Instead of the construction shown in Figure 1, the lower wall of the'expansion valve casing may be formed, as shown at 11 in Figure 4, and the port 21 may be connected by a pipe 41 with the refrigerating unit. This type may be used in either'a flooded or a dry system. 7 V

In the form shown in-Figureti, the valve casing comprises an upper wall 10 and a 1 lower wall 11 connected by tie rods or bolts 12. The wall 10 is formed with only one circular channel 13, and the wall 11 is formed with a similar channel 14 to receive the cylindrical glass wall 15. In this form, therefore,there is no outer chamber, but the refrigerant passesv from the :refrigeratmg unit directly baclrto the pump. This type of construction is for use in a dry system, and the pro-cooling efiect of the refrigerant is not utilized.

From the foregoing description, it will be seen that T have devised an expansion valve assembly which is simpleand practical in its construction, and in which the operation is plainlyvisible; This assembly is adapted to be used in any type of refrigerating system. The, operation .of the valve depends upon the action of a single movable member, the bellows which supports it. it is instantly responsive to variations in temperature and pressure, and the required degree of vacuum is maintained on the low side of the system at all times. The valve prevents any accumulation of lubricant on the high side of the system as it allows oil to pass to the boiler where a uniform liquid level is automatically maintained. All lubricant that is in excess of the amount required to maintain the given liquid level, in the boiler, is returned to the crank case of the pump along with the returning This circulation of the lubricating oil insures the smooth running of the refrigerating unit without any personal attention.

The valve is so constructed as to allow oil and liquid sulphur dioxide, or other refrigerant, to pass from the high side of the system, and will prevent any gas from passing with the liquid. This action maintains the pressure in the inner compartment of the valve, which is in reality a part of the high side of the system. The oil. and gas, as it passes through the outer compartment 18 of the valve, on its way from the boiler to the crankcase of the pump, increases the etliciency of the system by its pre-eooling eifect on the contents of the inner compartment. A vacuum is maintained in the boiler, but this does not in any way affect the operation of the valve.

The action of the valve, therefore, controlled by the temperature and pressure within the bellows, in conjunction with the pressure and temperature outside the bellows in the inner chamber, which is a part of the high side of the system, while the gas and oil pass from the boiler to the pump through the outer chamber, which is a part of the low pressure side of the system. Conditions may be such that the temperature and pressure may work either in conjunction, or as distinct and separate agents in the operation of the systems 7 While I have shown and described the invention as bestadapted for use in conjunction with the refrigerating system described in my above mentioned co-pending application, it is obvious that the same is capable of use in connection with any construction where a similar control. by temperature and pres sure is desired. It is also to be observed that various modifications may he made in the construction and arrangement of the various constituent parts withoutany material departure from the salient features thereof, or the recognized principles which characterize its operation. It is my purpose, therefore, to include all such modilical'irms within the scope of the appended claims.

That is claimed is:

'1. In an expansion valve assembly, the combination of a chamber having an inlet port in its upper wall and an outlet port in head and a lower head, means within the bellows to limit the longitudinal expansion thereof, means connected with the upper head for supporting the bellows, a valve secured to the lower head and controlling the I outlet port in response to variations in temperature or pressure within the chamber, and manually operable means for adjusting said bellows toward or away from the outlet port.

2. In an expansion valve assembly, the combination of a chamber having an inlet port and an outlet port, said outletport being at the bottom of the chamber, a bellows arranged vertically within the chamber and having an upper head and a lower head, means connected with the upper head for supporting the bellows, a valve secured to the lower head and controlling the outlet port in response to variations in pressure within the chamber, a stop member connected to the inside of the upper head, and a hook connected to the inside of: the lower head and engageable with said stop member to positively limit the longitudinal expansion of the bellows.

3. In an expansion valve assembly, the combination of an innerchamber having an inlet port and an outlet port, an outer chamber extending about the inner chamber and separated therefrom, means for connecting the inner chamber with the high pressure side of a refrigerating system, means connecting the outlet port with the low pressure side, a valve for said outlet port, means connected to the valve within the inner chamber and operable by variations in pressure or temperature to actuate said valve, and means for connecting said outer chamber respectively with the low pressure side of the system and the compressor.

4:. In an expansion valve assembly, the combination of an inner chamber having an inlet port to the upper part thereof and an outlet port from its bottom, a valve cooperating with the outlet port, means for controlling said valve in response to variations of pressure within the inner chamber, means for connecting said inlet port with the high pressure side of a refrigerating system, means for connecting said outlet port with thelow pressure side, an outer chamber extending about the inner chamber and separated therefrom, means for connecting the lower part of the outer chamber with the low pressure side of the system, and means for connecting the upper part of the outer chamber with the compressor.

5. In an expansion valve assembly, the combination of a casing comprising top and bottom walls with two transparent cylindrical concentric walls connecting the same to form inner and outer chambers, the inner chamber having an inlet port and an outlet port, means for connecting said inlet port with the high pressure side of a refrigerating system,means for connecting the outer port with the low pressure side, a valve for said outlet port, means for controlling the valve in response to variations of pressure in the inner chamber, and means connecting the outer chamber respectively with the low pressure side of the system and with the compressor.

In testimony that I claim the foregoing as my own, I have hereto affixed my signature.

SIDNEY EUGENE WILSON. 

